The present disclosure relates to image reading devices and image forming apparatuses.
An image reading device that reads an image formed on an original document is generally known. A technique to perform, in an image reading device, certain processing relating to punched holes is also known.
A known image reading device for example performs blank paper detection while excluding a region having punched holes. The image reading device excludes a rectangular region of an original document having punched holes, if any, from a target region of the blank paper detection. The rectangular region includes a region having the punched holes. If a total number of pixels within the target region of the blank paper detection that are counted with respect to a density range of zero to a specified density is greater than a threshold, the original document detected is determined to be blank paper.
This image reading device can reduce false detection of blank paper by excluding the region of the original document having punched holes from the target region of the blank paper detection.